After only a week of training, German military dogs detected the SARS-Cov-2 virus in saliva or secretions from the lungs of infected patients with an average accuracy rate of 94%. The hope is that more research will let us enlist the dogs in our fight to contain the virus.
Dogs have noses that put ours to shame. For starters, they have 300 million olfactory receptors in their noses, while we have only about six million, according to NOVA. When a dog inhales, it has a special system that splits the inhalation into an olfactory channel and a breathing channel. Once in the olfactory channel, the air travels through turbinates, a maze of bony structures that sorts the odor molecules and sends electrical signals to a part of the dog’s brain that is used to decode scent; this part of the canine brain is proportionally 40 times larger than ours. Beyond that, a dog can sniff up to 300 times per minute, allowing it to sample the scents around it continually.
This scent superpower has encouraged humans to enlist dogs to help with detecting everything from bombs and drugs to disease. Dogs have already been used to sniff out certain cancers, malaria, and Parkinson’s disease, according to the non-profit organization, Understanding Animal Research. Beyond that, they are also frequently used to alert epileptic patients to impending seizures.
Now, man’s best friend has earned another gold star for helping humans out.
A team of researchers showed that after only a week of training, eight Bundeswehr (German military) detection dogs were able to identify 157 positive SARS-CoV-2 samples and 792 negative samples correctly, while only getting the positive samples wrong 30 times, and the negatives wrong 33 times. SARS-CoV-2 is the virus that causes COVID-19.
“Dog odor detection is far better than the general public can imagine,” said Esther Schalke, a behavioral researcher and dog trainer who accompanied the project on the part of the Bundeswehr. “Still, we were amazed at how quickly our dogs could be trained to recognize samples from SARS-CoV-2 infected individuals. ”
During the testing, the dogs were presented with safe, deactivated strains of the virus in a unique machine that randomized the positions of the infected samples.
The researchers believe that further research and training could enable dogs to be used as pre-screeners to detect infected people in public venues such as stadiums and airports, as well as at border crossing checkpoints.
The work has been published in the journal BMC Infectious Diseases.
You can hear more from the researchers in the following video: Diagnoses by Dog Noses.